🪴 Hector's LearningHub

Search

SearchSearch

Containerizing the Tooling Web Application

Dec 14, 2024, 11 min read

(old Project 20)

PROJECT 20

In this project let us migrate the Tooling Web Application from a VM-based solution into a containerized one

Get Docker Engine in Ubuntu

hector@hector-Laptop:~$ docker --version
Docker version 20.10.12, build 20.10.12-0ubuntu2~20.04.1
hector@hector-Laptop:~$

I will use a pre-built MySQL database container, configure it, and make sure it is ready to receive requests from our PHP application.

To avoid having to run docker with sudo

sudo chmod 666 /var/run/docker.sock #changing permissions
sudo useradd -G docker $USER #add current user to group docker

Currently I have no images

hector@hector-Laptop:~$ docker images ls
REPOSITORY   TAG       IMAGE ID   CREATED   SIZE

Getting the image I need mysql/mysql-server:latest

hector@hector-Laptop:~$ docker pull mysql/mysql-server:latest
latest: Pulling from mysql/mysql-server
1866ca302f77: Pull complete
7208ad90232c: Pull complete
b2d9c817f662: Pull complete
3292176f57b6: Pull complete
d77130a2f17e: Pull complete
47bc31a509ca: Pull complete
fade2a0af17d: Pull complete
Digest: sha256:1a8d2a5584e53a42a43cbd430ae340a36942afee9e14a86624a2cb2d90ce655b
Status: Downloaded newer image for mysql/mysql-server:latest
docker.io/mysql/mysql-server:latest

Now I see the image I just downloaded

hector@hector-Laptop:~$ docker images
REPOSITORY           TAG       IMAGE ID       CREATED        SIZE
mysql/mysql-server   latest    5a9594052aec   3 weeks ago    438MB

deploying a new MySQL container
docker run --name <container_name> -e MYSQL_ROOT_PASSWORD=<my-secret-pw> -d <docker-image>

docker run --name MySQL -e MYSQL_ROOT_PASSWORD=Passw0rd! -d mysql/mysql-server:latest

MySQL container is running:

hector@hector-Laptop:~$ docker run --name MySQL -e MYSQL_ROOT_PASSWORD=Passw0rd! -d mysql/mysql-server:latest
ce2dcf1ec7aab8d2dd5c70919ead800fcdcbdc623a64b292a8876f26fcc0f746
hector@hector-Laptop:~$ docker ps -a
CONTAINER ID   IMAGE                       COMMAND                  CREATED          STATUS                             PORTS                       NAMES
ce2dcf1ec7aa   mysql/mysql-server:latest   "/entrypoint.sh mysq…"   31 seconds ago   Up 30 seconds (health: starting)   3306/tcp, 33060-33061/tcp   MySQL

Now I will do some cleaning to start fresh
Stopping all running containers docker stop $(docker ps -aq)
Remove all containers docker rm $(docker ps -aq)
(alternative I can copy paste individual Container ID)

CONNECTING TO THE MYSQL DOCKER CONTAINER

First, create a network
docker network create --subnet=10.0.0.0/24 tooling_app_network

I can double check with docker network ls

hector@hector-Laptop:~$ docker network ls
NETWORK ID     NAME                  DRIVER    SCOPE
8c221e829dfd   bridge                bridge    local
92a7c27b8b67   host                  host      local
7210e0bcf142   none                  null      local
79c067ecb744   tooling_app_network   bridge    local
hector@hector-Laptop:~$

Creating a new container mysql-server

export MYSQL_PW="Passw0rd!" #env variable to store root password
docker run --network tooling_app_network -h mysqlserverhost --name=mysql-server -e MYSQL_ROOT_PASSWORD=$MYSQL_PW -d mysql/mysql-server:latest

Flags used:

  • -d runs the container in detached mode
  • —network connects a container to a network
  • -h specifies a hostname
  • -e to set environment variable in the container

Double checking container creation docker ps -a

hector@hector-Laptop:~$ docker ps -a
CONTAINER ID   IMAGE                       COMMAND                  CREATED         STATUS                   PORTS                       NAMES
acbcd4888fe6   mysql/mysql-server:latest   "/entrypoint.sh mysq…"   7 minutes ago   Up 7 minutes (healthy)   3306/tcp, 33060-33061/tcp   mysql-server

Creating script create_user.sql that generates a user and database called hector

hector@hector-Laptop:~$ bat create_user.sql
───────┬─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: create_user.sql
───────┼───────────────────────────────────────────────────────────────────────────────────────────────────────────────────── 
   1   │ CREATE DATABASE hector;
   2   │ CREATE USER 'hector'@'%' IDENTIFIED BY 'password';
   3   │ GRANT ALL PRIVILEGES ON * . * TO 'hector'@'%';
   4   │
───────┴─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

Now I execute this script inside of the mysql-server container

hector@hector-Laptop:~$ docker exec -i mysql-server mysql -uroot -p$MYSQL_PW < ./create_user.sql #make sure no space after -p
mysql: [Warning] Using a password on the command line interface can be insecure.
hector@hector-Laptop:~$

Connecting to mysql-server using another container in interactive mode

docker run --network tooling_app_network --name mysql-client -it --rm mysql mysql -h mysqlserverhost -u hector -p

Flags used:

  • —name gives the container a name
  • -it runs in interactive mode and Allocate a pseudo-TTY
  • —rm automatically removes the container when it exits
  • —network connects a container to a network
  • -h a MySQL flag specifying the MySQL server Container hostname
  • -u user created from the SQL script
  • -p password specified for the user created from the SQL script

Connecting to mysql-server and displaying database hector I created there

hector@hector-Laptop:~$ docker run --network tooling_app_network --name mysql-client -it --rm mysql mysql -h mysqlserverhost -u hector -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 236
Server version: 8.0.29 MySQL Community Server - GPL
 
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
 
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
 
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
 
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| hector             |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
5 rows in set (0.00 sec)
 
mysql>

As long as we don’t exit, the container will run

 
hector@hector-Laptop:~$ docker ps -a
CONTAINER ID   IMAGE                       COMMAND                  CREATED          STATUS                 PORTS                       NAMES
9135fae03302   mysql                       "docker-entrypoint.s…"   19 seconds ago   Up 18 seconds          3306/tcp, 33060/tcp         mysql-client
acbcd4888fe6   mysql/mysql-server:latest   "/entrypoint.sh mysq…"   3 hours ago      Up 3 hours (healthy)   3306/tcp, 33060-33061/tcp   mysql-server

Prepare database schema

Cloned repo git clone https://github.com/hectorproko/tooling to path /home/hector

Creating an environmental variable for tooling_db_schema.sql’s path

hector@hector-Laptop:~/tooling/html$ export tooling_db_schema=/home/hector/tooling/html/tooling_db_schema.sql
hector@hector-Laptop:~/tooling/html$ echo $tooling_db_schema
/home/hector/tooling/html/tooling_db_schema.sql

Using the variable to execute script on mysql-server

docker exec -i mysql-server mysql -uroot -p$MYSQL_PW < $tooling_db_schema

Checking the new database created

docker exec -it mysql-server mysql -uroot -p$MYSQL_PW
mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| hector             |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| toolingdb          |
+--------------------+
6 rows in set (0.01 sec)
 
mysql>

Updating file tooling/html/.env

hector@hector-Laptop:~$ bat tooling/html/.env
───────┬────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: tooling/html/.env
───────┼────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ # input your environment variables
   2   │
   3   │ MYSQL_IP=mysql-server
   4   │ MYSQL_USER=hector
   5   │ MYSQL_PASS=password
   6   │ MYSQL_DBNAME=toolingdb
───────┴────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
hector@hector-Laptop:~$

Run the Tooling App

I will now containerize the application tooling by telling Docker how to pack the app into an image using a Dockerfile

hector@hector-Laptop:~/tooling$ bat Dockerfile
───────┬────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: Dockerfile
───────┼────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ FROM php:7-apache
   2   │ MAINTAINER Dare dare@zooto.io
   3   │
   4   │ RUN docker-php-ext-install mysqli
   5   │ RUN echo "ServerName localhost" >> /etc/apache2/apache2.conf
   6   │ RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
   7   │ COPY apache-config.conf /etc/apache2/sites-available/000-default.conf
   8   │ COPY start-apache /usr/local/bin
   9   │ RUN a2enmod rewrite
  10   │
  11   │ # Copy application source
  12   │ COPY html /var/www
  13   │ RUN chown -R www-data:www-data /var/www
  14   │
  15   │ CMD ["start-apache"]
───────┴────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
hector@hector-Laptop:~/tooling$

I begin by ensuring my current working directory is tooling which contains the Dockerfile

I’ll run the following command to build

docker build -t tooling:0.0.1 .

-t parameter is to tag the image as tooling:0.0.1 The . at the end, says to look for Dockerfile in the current working directory

Now using this new build I’ll run a container in interactive mode just to look inside -it

hector@hector-Laptop:~/tooling$ docker run --network tooling_app_network -p 8085:80 -it tooling:0.0.1
[Thu Jun 30 19:39:01.289793 2022] [mpm_prefork:notice] [pid 9] AH00163: Apache/2.4.53 (Debian) PHP/7.4.29 configured -- resuming normal operations
[Thu Jun 30 19:39:01.289822 2022] [core:notice] [pid 9] AH00094: Command line: 'apache2 -D FOREGROUND'

--network flag to make sure both Tooling app and database containers are in the same virtual network
-p flag to map the container port 80 to host port 8085

If everything works, I can open the browser and type http://localhost:8085

logo

PRACTICE TASK

Practice Task №1 – Implement a POC to migrate the PHP-Todo app into a containerized application.

Part 1

Tasks:

  1. Write a Dockerfile for the TODO app Repo Here
  2. Run both database and app on your localmachine Docker Engine
  3. Access the application from the browser

First I make sure I have my mysql-server container created/running with the .sql script executed

docker run --network tooling_app_network -h mysqlserverhost --name=mysql-server -e MYSQL_ROOT_PASSWORD=$MYSQL_PW-d mysql/mysql-server:latest
 
docker exec -i mysql-server mysql -uroot -p$MYSQL_PW < ./create_user.sql

The 3 files we need to focus on are:
Dockerfile
start-apache.sh
.env

#This portion of .env
DB_HOST=mysql-server
DB_DATABASE=hector
DB_USERNAME=hector
DB_PASSWORD=password

Now I will build my php-todo app image using docker build in the root directory of TODO app Repo where the desire Dockerfile file is located

docker build -t phptodo .

Double checking image was created

$ docker images | grep phptodo
phptodo                              latest       d11eee293df9   27 minutes ago      548MB

Using newly created image (phptodo) to start a container

docker run --network tooling_app_network -p 8085:8000 -it phptodo

logo

Part of the output:
Using Laravel to server the php application

Generating autoload files
> php artisan clear-compiled
> php artisan optimize
Generating optimized class loader
Nothing to migrate.
Application key [lG6XbWSiRUu19AeD49zXUu1NZtdd7F7j] set successfully.
Application cache cleared!
Configuration cache cleared!
Route cache cleared!
Laravel development server started on http://0.0.0.0:8000/
[Wed Jul  6 21:25:11 2022] PHP 7.4.30 Development Server (http://0.0.0.0:8000) started

logo

Part 2

Tasks:

  1. Created an account in Docker Hub
  2. Created a new DockerHub repository project20
  3. Pushed the docker images from local machine to the repository

Image I want to push is phptodo

hector@hector-Laptop:~$ docker images | grep phptodo
phptodo                              latest       d11eee293df9   20 hours ago    548MB
hector@hector-Laptop:~$

Authenticate docker logging docker login

$ docker login --username=hectorproko
Password:
WARNING! Your password will be stored unencrypted in /home/hector/.docker/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store
 
Login Succeeded

I’ll tag the image to specify the user, repo and name of image (at destination) using docker tag image ID hectorproko/project20:phptodo

hector@hector-Laptop:~$ docker tag d11eee293df9 hectorproko/project20:phptodo
hector@hector-Laptop:~$ docker images | grep phptodo
hectorproko/project20                phptodo      d11eee293df9   21 hours ago    548MB
phptodo                              latest       d11eee293df9   21 hours ago    548MB

Now I push image hectorproko/project20:phptodo to repo project20 (all specified in th e tag)

hector@hector-Laptop:~$ docker push hectorproko/project20:phptodo
The push refers to repository [docker.io/hectorproko/project20]
a4a30dbdf285: Pushed
8bbf535c1f67: Pushed
c36235383c8e: Pushed
d10e1ab513aa: Mounted from library/php
cf5a028805be: Mounted from library/php
31ee2ad0069c: Mounted from library/php
3a6511781124: Mounted from library/php
dd5f6ab1e450: Mounted from library/php
49269d9adf35: Mounted from library/php
6fd16b261e9c: Mounted from library/php
cefda33a1738: Mounted from library/php
08249ce7456a: Mounted from library/php
phptodo: digest: sha256:422f9c3adbe810f3ed0976a6a58a3f97e7815913da5f9639645aac198bc83ade size: 2834
hector@hector-Laptop:~$

phptodo: digest: sha256:422f9c3adbe810f3ed0976a6a58a3f97e7815913da5f9639645aac198bc83ade size: 2834

logo

Click See all

logo

Part 3

Tasks:

  1. Write a Jenkinsfile that will simulate a Docker Build and a Docker Push to the registry
  2. Connect your repo to Jenkins
  3. Create a multi-branch pipeline
  4. Simulate a CI pipeline from a feature and master branch using previously created Jenkinsfile
  5. Ensure that the tagged images from your Jenkinsfile have a prefix that suggests which branch the image was pushed from. For example, feature-0.0.1.
  6. Verify that the images pushed from the CI can be found at the registry.

Created a new branch docker_job in repo php-todo just to hold a Jenkinsfile

To work and test on this file I’ll start a Jenkins instance in my local machine (has Docker Engine) using .war file

Instructions
Download the .war and run java -jar jenkins.war

The Jenkins job has to be Multibranch Pipeline or environment variable BRANCH_NAME will not work
logo

Creating DockerHub credentials

In the Snippet Generator “Sample Step: withCredentials: Bind credentials to variables” I generate username and password

Now I can use the credentials to login and push

withCredentials([usernamePassword(credentialsId: 'DockerHubLogIn', passwordVariable: 'password', usernameVariable: 'username')]) {
  sh "docker login -u ${username} -p ${password}"
  sh "docker push hectorproko/project20:php-todo-${env.BRANCH_NAME}-${env.BUILD_NUMBER}"
}

The credentials can now be found in Manage Jenkins > Manage Credentials
logo

I do three sample builds
logo

The three builds appear in DockerHub
logo

The rest of the Jenkinsfile

Using an environment variable repo can get cloned with different branches
stage('Checkout SCM')

git branch: "${env.BRANCH_NAME}", url: "https://github.com/hectorproko/php-todo.git"`

Here I use two env variables, branch and build number to tag the image
stage('Docker Image Build')

sh "docker build -t hectorproko/project20:php-todo-${env.BRANCH_NAME}-${env.BUILD_NUMBER} ."`

Here I create the container using the same two variables to identify the image after stopping and removing previous container so there is no conflict
stage('Start Container')

sh "docker stop php-todo && docker rm php-todo" 
sh "docker run -d --name php-todo --network tooling_app_network -p 8085:8000 hectorproko/project20:php-todo-${env.BRANCH_NAME}-${env.BUILD_NUMBER}"

Puhing image to DuckerHub (Already shown above)
stage('Push Image')

Using variables to identify the image to delete
stage('Delete Image')

sh "docker rmi -f hectorproko/project20:php-todo-${env.BRANCH_NAME}-${env.BUILD_NUMBER}"`

Using Docker-Compose to define and run the multi-container Docker application Tooling

I’ll use a YAML file tooling.yml to configure the application’s services. Then, with a single command, it will create and start all the services from the configuration.

First I want to convert the container mysql-server to an image to reuse since it already has the needed database after executing script tooling_db_schema.sql

This new image is tagged mysql-server:tooling

hector@hector-Laptop:~/tooling/html$ docker commit 598c041e96c5 mysql-server:tooling
sha256:55c432b0319b60f0ac2f5ec14ece6c2095b15a0fdecfd9cf17c4687a7ee53be6

Need to update tooling/html/.env to a different MySQL server name dockercompose_db_1

hector@hector-Laptop:~$ bat tooling/html/.env
───────┬─────────────────────────────────────────────────────────────────────────────────────────
       │ File: tooling/html/.env
───────┼─────────────────────────────────────────────────────────────────────────────────────────
   1   │ # input your environment variables
   2   │
   3   │ MYSQL_IP=dockercompose_db_1
   4   │ MYSQL_USER=hector
   5   │ MYSQL_PASS=password
   6   │ MYSQL_DBNAME=toolingdb
───────┴─────────────────────────────────────────────────────────────────────────────────────────
hector@hector-Laptop:~$

Now we can execute the tooling.yml configuration with Docker-Compose to bring the tooling application up
docker-compose -f tooling.yml up -d 

hector@hector-Laptop:~/tooling$ docker-compose -f tooling.yml up -d
Creating dockercompose_db_1 ... done
Creating dockercompose_tooling_frontend_1 ... done

We can see both containers running

hector@hector-Laptop:~/tooling$ docker container ls
CONTAINER ID   IMAGE                            COMMAND                  CREATED         STATUS                   PORTS                                   NAMES
b9d6940f7c30   dockercompose_tooling_frontend   "docker-php-entrypoi…"   2 minutes ago   Up 2 minutes             0.0.0.0:8085->80/tcp, :::8085->80/tcp   dockercompose_tooling_frontend_1
1f9febd04ba1   mysql-server:tooling             "/entrypoint.sh mysq…"   2 minutes ago   Up 2 minutes (healthy)   3306/tcp, 33060-33061/tcp               dockercompose_db_1

This time I use a terminal browser Lynx to test page
logo

Graph View

Backlinks